package com.yuhj.cateyemovie.effect;

import android.support.v4.view.ViewPager.PageTransformer;
import android.view.View;

/**
 * @name DepthPageTransformer
 * @Descripation <br>
	深入淡出
 * @author 禹慧军
 * @date 2014-11-5
 * @version 1.0
 */
public class DepthPageTransformer implements PageTransformer {
	private static float MIN_SCALE = 0.5f;

	
	@Override
	public void transformPage(View view, float position) {
		int pageWidth = view.getWidth();
		if (position < -1) { // [-Infinity,-1)
								// This page is way off-screen to the left.
			view.setAlpha(0);
			view.setTranslationX(0);
		} else if (position <= 0) { // [-1,0]
									// Use the default slide transition when
									// moving to the left page
			view.setAlpha(1);
			view.setTranslationX(0);
			view.setScaleX(1);
			view.setScaleY(1);
		} else if (position <= 1) { // (0,1]
									// Fade the page out.
			view.setAlpha(1 - position);
			// Counteract the default slide transition
			view.setTranslationX(pageWidth * -position);
			// Scale the page down (between MIN_SCALE and 1)
			float scaleFactor = MIN_SCALE + (1 - MIN_SCALE)
					* (1 - Math.abs(position));
			view.setScaleX(scaleFactor);
			view.setScaleY(scaleFactor);
		} else { // (1,+Infinity]
					// This page is way off-screen to the right.
			view.setAlpha(0);
			view.setScaleX(1);
			view.setScaleY(1);
		}
	}

}